1. Field of the Invention
The present invention relates to a stereoscopic camera apparatus for obtaining a stereoscopic image and, more particularly, to a stereoscopic electronic camera apparatus which incorporates cameras and can commonly adjust directions of the cameras.
2. Description of the Related Art
Recently, as a technique for obtaining a stereoscopic image, a stereoscopic camera apparatus comprising two cameras is developed. As is well known, the stereoscopic image is obtained as follows. Two independent cameras are arranged to be separated at a predetermined distance, an identical object is picked up by the two cameras, and video signals obtained from these cameras are subjected to time-divisional processing by a time-division circuit. With this time-divisional processing, a stereoscopic image can be obtained by utilizing a difference in image due to a parallax of man's eyes, and a convergence visual angle. Such a technique is described in U.S. Pat. No. 4,021,846. For example, video signals from two cameras which are arranged to be separated at a predetermined interval and to have a predetermined convergence angle are converted to stereoscopic video signals by a time-divisional processing circuit. An image is displayed on a monitor television based on the converted video signals. A user views the display screen of the monitor television through liquid-crystal shutter spectacles driven in synchronism with the time-divisional processing of the time-divisional processing circuit, thus achieving a stereoscopic view.
The directions, i.e., vertical and horizontal directions of the two independent cameras must be adjusted so that images can accurately coincide with each other on an imaginary plane to achieve a stereoscopic view. More specifically, the interval and convergence angle between the two cameras (lenses) must be adjusted so as not to cause offsets in the vertical and horizontal directions of the cameras and a rotational offset about the optical axis of each camera.
However, since the two independent cameras are mounted on separate pan heads, when the directions are adjusted by moving these pan heads, the interval and convergence angle of the cameras are shifted during adjustment, resulting in unbalance. Therefore, the adjusting operation is very difficult to achieve, and requires a long period of time.